基于瞬态动力学的弹载MEMS陀螺抗冲击特性分析

Analysis of Anti-shock Characteristic on Missile Borne MEMS Gyroscope with Transient Dynamic Method

摘要:

针对微机械(MEMS)陀螺在冲击环境下的适应性问题，对导弹发射初始段MEMS陀螺的抗冲击特性进行了分析。运用傅里叶变换分析了发射初始段的冲击载荷特征；采用瞬态动力学方法结合有限元分析，综合考虑了冲击信号特征、金属壳体力学传递、MEMS陀螺抗冲击指标等因素，计算了弹载MEMS陀螺安装处的冲击响应。实验结果表明：由于高频冲击信号与惯性测量单元金属壳体的二阶模态频率相近，使得弹载MEMS陀螺所承受的力学冲击量级放大了约4倍，达到879 g，致使发射初始段弹载MEMS陀螺存在失效风险，因此在工程应用时应采取一定的防护措施。

Abstract:

Aiming at the adaptability of missile-borne micro-electro-mechanical systems (MEMS) gyroscope in shock environments, the anti-shock characteristic of MEMS gyroscope is analysed during the initial stage of missile launch. The shock signal characteristics are analysed using Fourier transform, and the shock response of the position where the missile-borne MEMS gyroscope installed is calculated by the transient dynamics method combined with finite element analysis, factors such as the characteristics of the shock signal, the mechanical transmission of the metal shell and the index of MEMS gyroscope are comprehensively considered. The experimental results show that the frequency is close between the high-frequency signals and the second order modal of the inertial measurement unit (IMU) metal shell, the mechanical shock borne MEMS gyroscope is amplified by about 4 times, reaching 879g, which leads to a risk of MEMS gyroscope failure in the initial launch stage. Therefore, some protective measures should be taken in engineering application.